A screen printing machine is an apparatus for printing paste such as solder on an electrode on a substrate held in a substrate holding part, and is configured so that a mask in which a pattern hole according to arrangement of the electrode of the substrate is formed is brought into contact with the substrate so as to vertically match the electrode with the pattern hole and then a squeegee is slid on the mask supplied with the paste and the paste is scraped and is transferred to the electrode of the substrate through the pattern hole of the mask.
In such a screen printing machine, the mask is held in a horizontal attitude by a mask holder formed over the substrate holding part. The mask holder is configured to have right and left side support parts for supporting both right and left sides of the mask when viewed from an operator, a back edge stopper which is provided on the back of the right and left side support parts and is abutted on the back edge of the mask whose both right and left sides are supported by the right and left side support parts, and a front edge stopper which is provided on the front of the right and left side support parts and is abutted on the front edge of the mask (for example, Patent Reference 1).
Since it is necessary to change the mask according to a kind etc. of the substrate targeted for screen printing, the right and left side support parts of the mask holder are configured so that a distance between a pair of rail-shaped members for supporting both right and left sides of the mask can be changed according to a dimension in a right-and-left direction of the mask, and a position in a front-back direction of the front edge stopper can also be changed according to dimensions of the mask. Also, some mask holders can change a position in a front-back direction of the back edge stopper.